Corrugating roller is a key component in corrugated carton production. The function of corrugating roller is to process corrugating medium paper into the required flute, and fixed medium paper to complete the gluing and surface operation. In order to improve wear resistance and reduce wear, the roller surface must be both strong and durable. Strong but not durable will cause mechanical damage (breakage or peeling) to the surface of the roll. This damage will accelerate roller wear. In the daily use of corrugating roller, service life can be extended through some simple ways.
Because corrugating rollers will be worn, the surface of the rollers will obviously appear ladder like pattern. Wear is the most serious in the middle of the roller, especially in the paper edge through the part of the roller surface is the most obvious. This will result in uneven pressure on the pressure roller clamps and difficulty in aligning the glue on the floor. When this wear affects the quality of the board, even if the thickness is still within the acceptable range, then it is necessary to replace the roller.
In order to overcome this problem, diamond paste can be used to grind or a small amount of material can be removed from the flute point at the journal (0.05mm). This operation is very difficult and requires a high level of skill in order not to rub off the important coating on the corrugating form.
As with many maintenance methods, there is no need to maintain badly worn rollers with this method. Some factories produce small fixtures that can be mounted ona single-sided machine to make grinding more accurate and easy. The service life of the uncoated roller can be extended significantly by careful grinding.
The pressure of the corrugating roll can be adjusted by changing the paper frame or core paper grade (the pressure should be appropriately reduced to prevent metal and metal contact at the shaft neck).
When required, correct adjustments can reduce journal damage and extendroll life. More important is to ensure that the rollers are placed in parallel in the machine. This can be detected by the electric newspaper, the electric newspaper into the roller, can show the relative position of the upper pressure roller and the lower pressure roller, when the roller is first installed, you can also use this electric newspaper.
In order to ensure the service life of rollers, they must be placed in parallel. In future checks, any shift indicates a potential problem with the machine.
The presence of metal particles larger than 0.5mm will cause damage to the roll. The roller and single-side machine should be kept clean enough to avoid unnecessary large particles of impurities passing between the rollers.
Internal Monitoring of Roll Wear
Reinforced steel roll wear is linear, so it is necessary to regularly detect the corrugation height, accurately infer the life expectancy of the roll and replacement date. A dial scale or traditional depth micrometer may be used in conjunction with a small pin (radian less than the radian of the valley) for measurement. Rollers should be checked periodically to detect wear rates between each fixed paper frame. If running normally, the wear rate of the roll should correspond to the percentage of each fixed paper frame running on the roll.
Different coating rollers (chrome or tungsten carbide) are tested slightly differently. Coating roll wear rate is much smaller than the steel base roll. In this way, in the absence of specific equipment, this small wear rate in a single machine is difficult to accurately measure. This means that coating integrity is an important guide to rolllife. The integrity of the coating can be detected by applying copper sulfide tothe surface of the roll (which is available from the laboratory supplies supplier).
If the coating is complete, copper sulfide will remain blue. If the stainless steel is exposed, the copper sulfide will turn brown after twominutes and stain the surface of the stainless steel. The first wear on the coating should be at the edge of the groove in the middle of the roll.
Other ways to improve roll life include optimizing the Angle arc, which is the best compromise between wear and shrinkage, and improving surface smoothness to minimize friction coefficient between paper and roll and continuous paper tension. The last factor that affects the life of the roll is the smooth running performance of the rollitself at any running speed. Vibration or unstable operation of the roller will increase the impact of hammer tip at both ends of the roller, and lead topremature fracture of the surface of the roller, greatly reducing the servicelife of the roller.
Inspection of Corrugating Roll During Installationand Commissioning：
Inspection and maintenance of corrugating roll during installation and commissioning;
Inspection and maintenance items before installation;
Clean and inspect corrugating surface appearance of corrugating roller (including plating quality);
Clean and inspect fastening parts of connection (including internal and external threads);
Check the outer diameter and middle height of corrugating roller(the whole roll surface is divided into more than five measuring points from both ends to the middle). The detection points of middle and high rollers must be odd, and the data of middle and high rollers should be symmetrical on both sides. With the corresponding specifications of the outside micrometer measurement (outside micrometer can be bought from general mechanical and electrical companies );
Check the height of corrugating roller. Needle type depth dial meter measurement.
Clean and check the outer diameter and appearance of each shaft of corrugating roller. Measure the out erdiameter with the corresponding micrometer.
Check the parallelism of the upper and lower corrugating rollers (generally, corrugating rollers in contact with the pressure rollers are not of medium or high height, so they are the reference rollers for installation. The corrugating roll with the middle height has an eccentric adjustment mechanism to adjust the two roller sparallel). Pressure sensitive paper, carbon paper or fuse can be used to determine and adjust the corrugating shape and side indentation of the corrugating shape of the two layers of cardboard during production operation;
Check the parallelism between the upper and lower corrugating rollers and the pressure rollers. During the operation of the upper and lower corrugating rollers and the pressure rollers, the axis of the three rollers should be parallel and the line pressure shouldbe uniform. It can be judged according to the indentation of two layer corrugating board linerboard that being composited , and adjust the pressure atboth ends of the pressure system;
Check the parallelism of corrugating roller and glue roller, according to the gap requirements of different corrugating type on the amount of glue, check and adjust the gap between corrugating roller and glue roller with a plug gauge or corrugating paper from both ends;
Check and adjust the corrugating roller and guide paper coated device, the relative position of apositive pressure paper guide or a negative pressure paper guide, vacuum adsorption device or clearance between positive pressure cavity with corrugating roller and pressure roller seal canbe adjusted according to the testing requirements of the production line , to control air pressure and leak, in order to ensure that the ironing corrugating paper can be closely sticky to the corrugating roller to complete gluing and composite drying process:
The above items must be fixed with their limit devices after debugging;
Bearings of corrugating rollerand pressure roller and other roller must meet the requirements of accuracy, high temperature grease must be selected high quality, oil seal to seal well.
Daily inspection and maintenance of corrugating roller during normal production and operation;
Before operation and production;
Check and ensure thecleanliness of each roll surface;
Check and ensure the correct position of each roller;
Check and ensure that the relevant devices (paper guide copper plate device, positive pressure paper guide device or negative pressure paper guide device, etc.) are in the correct position, Check the wear condition and adjust it;
Check and ensure proper position of adhesive system and good preparation of adhesive;
Check and ensure the lubrication oil supply preparation is normal;
Check and ensure the normal pressure and hydraulic system;
Check and ensure the heating system is normal;
During Operation and Production:
Check and control the temperature, those vaper-heated should prevent condensation water from being discharged and pipe valve leakage, we should also patrol and ensure steam supply pressure;
Check and control the humidity of corrugating medium and linerboard;
Check and control the operation position of corrugating medium and linerboard, both ends of the edge is neat;
Check and control flute shape accuracy of corrugating board , no high or low flute and flute collapse ;
Check and control the composite strength and the evenness of gluing of corrugating medium and linerboard ;
Check and control indentation of linerboard;
Check and control the smooth circulation of glue supply system;
Patrol inspection, ensure the smooth operation of machinery, no abnormal impact noise;
Inspect each lubrication oilsupply system to ensure normal operation;
Inspect the air pressure and hydraulic system to ensure that the work is normal and there is no leakage.
When Production is Stopped;
Close the heating system of theroller;
Close the pressure at which the roller is pressurized or hydraulic system;
Stop glue circulation, glue system separated from corrugating roller. Clean gluing system (including glue-feeding system);
Stop corrugating roller running when corrugating roller cooling below 40 ℃, cleaning roller surface and leading paper coins and confetti trash inside positive pressure ornegative pressure device ;
Keep good lubrication and refueling.
Above is the general principles of qualified corrugating rollers in the correct use and daily maintenance, and the basic environmental conditions affecting the service life of corrugating rollers. In corrugating board production industry, many enterprises has accumulated a lot of scientific management experience which is worth learning and promoting, companies can learn from each other.
As long as to continuous monitoring and improving the use environment and conditions of corrugating roller in the daily production process and production gap, and carry out strictly daily maintenan cescientifically and seriously, corrugating roller will certainly play its due role for the high yield and low consumption of corrugating board production enterprises.
Due to the structure and forms of corrugating board production line is different, some concrete and detailed useand maintenance of corrugating rollers and debugging methods need to be told to professional production maintenance services company, according to the actual condition of corrugating board production line and the corrugating roller concrete usage, so as to get satisfactory response and timely service and help.